Element

Element is the most general base class from which all objects in a Document inherit. It only has methods and properties common to all kinds of elements. More specific classes inherit from Element. For example, the HTMLElement interface is the base interface for HTML elements, while the SVGElement interface is the basis for all SVG elements. Most functionality is specified further down the class hierarchy.

Languages outside the realm of the Web platform, like XUL through the XULElement interface, also implement Element.

Removed the following methods: closest(), setIdAttribute(), setIdAttributeNS(), and setIdAttributeNode().
Removed the schemaTypeInfo property.
Modified the return value of getElementsByTag() and getElementsByTagNS().
Moved hasAttributes() from the Node interface to this one.
Inserted insertAdjacentElement() and insertAdjacentText().

Added the following methods: setIdAttribute(), setIdAttributeNS(), and setIdAttributeNode(). These methods were never implemented and have been removed in later specifications.
Added the schemaTypeInfo property. This property was never implemented and has been removed in later specifications.

[1] Internet Explorer 7 and 8 incorrectly return the comments as part of the children of an Element. This is fixed in Internet Explorer 9 and later.

[2] Chrome 16 allowed webkitRequestPointerLock() only in fullscreen; Chrome 21 for trusted web site (permission asked); Chrome 22 allowed it by default for all same-origin document; Chrome 23 allowed it in sandboxed <iframe> if the non-standard value webkit-allow-pointer-lock is set to the sandbox attribute.